How do the caller tell if S returned a scalar or an array?
I presume you mean list where you wrote array.

The answer is, it's actually not up to S. If S is called in scalar context, a scalar is returned. If S is called in list context, a list is returned. If S is called in void context (a special case of scalar context), nothing is returned.

In reply to Re: Detecting type of output from subs by JavaFan
in thread Detecting type of output from subs by mogul

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